Organic solar cells and polymer solar cells are built from thin films of organic semiconductors such as polymers and small-molecule compounds. Although energy conversion efficiencies achieved to date using conductive polymers are low compared to inorganic materials, such cells are beneficial for applications where mechanical flexibility or weight are required or desired. Furthermore, polymeric solar cells are generally lower in cost to manufacture than solar cell of polysilicon or other alternate designs.
Recently, there has been a drive to integrate solar cell technology into architecture, automobiles, and portable devices including clothing. Many designers for such applications are increasingly looking to flexible photovoltaic devices. One goal in this direction is that the desired appearance of the article define the appearance of the photovoltaic device, rather that the appearance of the photovoltaic device dictating the appearance of the article.
A typical solar cell or other photovoltaic device is often either blue-black or reddish-brown in color. To achieve other colored cell, a transparent colored layer, for example a pigmented anti-reflective coating, can be placed over the device. In other cases, a colored layer is placed over non-energy generating portions of the device. Recently, dye-sensitized cells using different colored dyes have been used to form cells with various desired colors. Recently camouflage solar panels have been formed in this manner. However, polymeric solar cells, where the device's color results from the inherent color of the polymer, have not been used to form photovoltaic devices with a pattern of colors, such as camouflage. Where specific colors are available, it is desirable to tune the color or intensity systematically such that the color can match that desired for a given segment of the article covered with the photovoltaic device.